The federal government is extending an olive branch to British Columbia in an attempt to tame the building tension over the Trans Mountain pipeline expansion project.

Environment and Climate Change Minister Catherine McKenna published an open letter to B.C. Environment Minister George Heyman on Thursday outlining the steps Ottawa has taken to prepare for a potential spill and offering scientific collaboration with the province to ensure its concerns are being addressed.

In the letter, McKenna restates her commitment to the pipeline project, calling it “vital infrastructure,” while noting the federal government has a “strong regime in place” to protect the environment.

She underscored the government’s dedication to developing resources in a manner that is “informed by rigorous science and evidence” and proposed establishing a joint scientific advisory council between Ottawa and the province of B.C.

McKenna welcomed more collaboration to ensure the province’s concerns are addressed in a “meaningful way.”

There has been ongoing tension between the country’s westernmost provinces over the $7.5-billion project after Kinder Morgan set a May 31 deadline to get the clarity it needs to proceed without exposing shareholders to undue risk.

The letter comes just hours before B.C. prepares to unveil the details of its reference case that questions whether the province has the power to regulate the flow of diluted bitumen across provincial borders.